[K12OSN] Need advice on recovering from failed boot disk

[Les Mikesell]

On 8/15/2011 10:28 AM, Carl Keil wrote:
>
> Anyway, now I'm looking for a little more philosophical advice. I used
> to run k12ltsp on this server, but don't any more. Now it's a
> web/samba/mythtv box for my home. If it was you, and your old k12-centos
> 5.3 box ate it, but you had homes, web root, samba shares and your
> mythtv shows on separate drives, (and many complete backups via
> BackupPC) would you take the opportunity to upgrade to centos 5.6 or 6.0
> or would you try to get back to 5.3 so you didn't break all that stuff
> via new versions of php, mysql, samba (prolly not an issue) and mythtv?
> What's the smart move here? Also, do you think there'll be a problem
> going to 64 bit, when the old install was 32 bit? I can't see why that
> would be an issue since basically I'm restoring functionality to content
> that I saved. If I go, for example from 32-bit Centos 5.3 to 64-bit
> Centos 6 will I still just be able to restore my /etc config files from
> backup and proceed on my merry way? Or will I have to go into each one
> and cut and paste relevant sections into new config files with differing
> formats, places on the drive, etc.

The first bit of advice would be to install on RAID1 mirrors if it holds 
your only copy of something, but backups are still important...  If you 
are happy with the current functionality, installing a 32-bit 5.6 is 
probably the fastest way to get back in operation. There might be a 
surprise or two in the config files between 5.3 and 5.6 (which you 
deserve for not doing timely 'yum updates' but I'd expect it to be 
easily fixed.   The switch to 6.0 would be more drastic and at this 
point you might as well wait for 6.1 and its fixes.  Mythtv sounds like 
the only thing not from the standard repositories, so make sure you can 
get that working again first.

> Also, How do you tell if your hardware should get a 64 bit centos or
> not? I'm not positive about my system. I think it's a Pentium D dual
> core. Obviously I'd check for sure before proceeding. But what's
> considered the minimum CPU that actually works with 64 bit Centos?

Boot from live or rescue media to a point where you can run 'cat 
/proc/cpuinfo' and look for 'lm' in the flags.  The other interesting 
flag is 'vmx' (intel) or 'svm' (amd) which will tell you if it can run a 
64-bit guest as a virtual machine.  Some processors can run 64 bit 
natively but not virtualize them.

-- 
   Les Mikesell
    lesmikesell at gmail.com